An example of a three-dimensional article manufacturing method is additive manufacturing, in which a three-dimensional article is manufactured by sequentially stacking layers of materials for forming a three-dimensional article to be formed of multiple layers. Stereo lithography (SL), selective laser sintering (SLS), fused deposition molding (FDM), and the like are known as forms of additive manufacturing. For example, in the manufacturing apparatus that is disclosed in PTL 1, a flat plate-shaped material formed by metal and resin powder materials being pressed is placed on a stage capable of moving in three axial directions. This flat plate-shaped material is melted by being exposed to laser light, and solidifies with time to become a layered article (referred to as a “flat plate-shaped material member” in PTL 1). Then, the manufacturing apparatus stacks the next flat plate-shaped material member after flattening the surface of the flat plate-shaped material member. The manufacturing apparatus joins the new portion to the already-shaped portion by exposing the stacked flat plate-shaped material member to laser light to cause the flat plate-shaped material member to melt and subsequently solidify. The three-dimensional article is manufactured by the stacking, melting, solidifying, and flattening of the flat plate-shaped material member being sequentially repeated.
PTL 1: JP-A-2011-241450